I'd agree with JohnKSa. Perceived recoil may happen after the bullet leaves the barrel, but actual recoil starts as soon as the bullet starts moving. At any rate, recoil shouldn't affect group size, as recoil itself (and hence muzzle movement during recoil) should be consistent from shot to shot.

You mentioned several times that recoil is significant. As mentioned, relative to other centerfire handguns, a serviced-sized 9mm should have pretty mild recoil. Relative to your M41 .22LR, it'll be stronger, of course, so I suspect you're comparing recoil to your M41. Nonetheless, recoil affects accuracy only via the shooter, i.e. a flinch. If you're flinching, try simply shooting into the berm or a blank target to get accustomed to the blast & recoil of your 9mm. Once your mind gets used to the idea that the blast & recoil won't hurt you, you'll begin to flinch less.